''Cladoceramus'' is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of fossil marine

pteriomorphia The Pteriomorphia comprise a subclass of saltwater clams, marine bivalve molluscs. It contains several major orders, including the Arcida, Ostreida, Pectinida, Limida, Mytilida, and Pteriida. It also contains some extinct and probably ...

bivalve Bivalvia () or bivalves, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class (biology), class of aquatic animal, aquatic molluscs (marine and freshwater) that have laterally compressed soft bodies enclosed b ...

s that superficially resembled the related winged pearly oysters of the

extant Extant or Least-concern species, least concern is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Exta ...

genus '' Pteria''. They lived in the

Santonian The Santonian is an age in the geologic timescale or a chronostratigraphic stage. It is a subdivision of the Late Cretaceous Epoch or Upper Cretaceous Series. It spans the time between 86.3 ± 0.7 mya ( million years ago) and 83.6 ± 0.7 m ...

stage of the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

Description

Adult shells of ''Cladoceramus'' are small to very large size (more than in length). Many species with fine, discrete, juvenile ornamentation on umbo, consisting of closely and evenly to subevenly spaced raised concentric growth lines without rugae. Posterior auricle well-defined, triangular, separated from disc by auricular sulcus; a post-umbonal sulcus occurs in some species, as do very small anterior auricles ("ears").Lower Turonian Euramerican Inoceramidae: A morphologic, taxonomic, and biostratigraphic overview
A report from the first Workshop on Early Turonian Inoceramids (Oct. 5-8, 1992) in Hamburg, Germany; organized by Heinz Hilbrecht and Peter J. Harries

Biostratigraphic significance

The first appearance of the species ''

Cladoceramus undulatoplicatus ''Cladoceramus'' is an extinct genus of fossil Marine (ocean), marine pteriomorphian bivalves that superficially resembled the related winged pearly oysters of the Extant taxon, extant genus ''Pteria (bivalve), Pteria''. They lived in the Santoni ...

'' marks the beginning of the

stage.

Distribution

Fossils of the genus have been found in:''Cladoceramus''
at

Fossilworks Fossilworks was a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database, a large relational database assembled by hundreds of paleontologists from around the world. History Fossilworks was cr ...

.org * Matulla Formation, Egypt ;United States * Forbes Shale, California * Smoky Hill Shale,

Niobrara Formation The Niobrara Formation , also called the Niobrara Chalk, is a geologic formation in North America that was deposited between 87 and 82 million years ago during the Coniacian, Santonian, and Campanian stages of the Late Cretaceous. It is com ...

, Colorado and New Mexico *

Austin Chalk The Austin Chalk is an upper Cretaceous geologic formation in the Gulf Coast region of the United States. It is named after type section outcrops near Austin, Texas. The formation is made up of chalk and marl. Fossils The putative galloansera ...

, Texas *

Mancos Shale The Mancos Shale or Mancos Group is a Late Cretaceous (Upper Cretaceous) geologic formation of the Western United States. The Mancos Shale was first described by Cross and Purington in 1899 and was named for exposures near the town of Mancos, C ...

, Wyoming

References

{{Taxonbar, from=Q105063205 Inoceramidae Monotypic prehistoric bivalve genera Index fossils Fossils of Egypt Cretaceous California Paleontology in California Cretaceous Colorado Paleontology in Colorado Cretaceous geology of New Mexico Paleontology in New Mexico Cretaceous Texas Paleontology in Texas Paleontology in Wyoming Prehistoric bivalves of North America Fossil taxa described in 1961